In the prior art, a space-forming member is provided in a header of a heat exchanger connected to a plurality of heat transfer tubes in order to form a plurality of spaces in the header.
A header of a heat exchanger disclosed in, e.g., Japanese Laid-open Patent Publication No. 2013-130386 has as a space-forming member in the header interior a vertical partition plate extending along a longitudinal direction of the header and a horizontal partition plate extending along a direction intersecting the vertical partition plate. In Japanese Laid-open Patent Publication No. 2013-130386, the vertical partition plate enters into a slit of the horizontal partition plate, and an end part of the vertical partition plate is made to contact the bottom surface of the header, whereby the vertical partition plate is held in position.
A header of a heat exchanger disclosed in Japanese Laid-open Patent Publication No. 2009-97776 has as a space-forming member a partition plate extending along a longitudinal direction of the header. The partition plate in Japanese Laid-open Patent Publication No. 2009-97776 is positioned between two outline members having a substantially E-shaped cross-section and is joined to an outer surface of one outline member and to an inner surface of the other outline member.